Expression of miR-155 and miR-146a in the saliva of patients with periodontitis and its clinical value.

Objective: To explore the significance of microRNA-155 (miR-155) and microRNA-46a (miR-46a) in the diagnosis of periodontitis (PD).

Methods: A total of 41 patients with PD admitted to our hospital between September 2017 and August 2019 were enrolled into an observation group (obs group), and 35 healthy individuals during the same period were enrolled into a control group (con group). A qRT-PCR assay was carried out to quantify miR-155 and miR-146a expression, and the relationship between the expression of miR-155 and miR-146a and severity and clinical indicators of PD was analyzed.

Results: The obs group showed significantly higher expression of saliva miR-155 and miR-146a than the con group (<0.05), and the expression of them was positively correlated with the severity of their PD. It was also positively correlated with gingival index (GI), attachment loss (AL), plaque index (PLI), probing depth (PD), and bleeding on probing (BOP) of them. Additionally, according to the receiver operating characteristic (ROC) curves, the area under the curve (AUC), specificity, and sensitivity of miR-155 in diagnosing PD were 0.887, 78%, and 97.14%, respectively, and those of miR-146a in diagnosing PD were 0.745, 58.54%, and 88.57%, respectively.

Conclusion: MiR-155 and miR-146a were both highly expressed in the saliva of patients with PD, and the expression of them was positively correlated with the severity and clinical indexes of PD, so miR-155 and miR-146a might be involved in the development and progression of PD.